


Zim's Grim adventures with Billy and Mandy

by MopeyZim



Category: Grim Adventures of Billy & Mandy, Invader Zim
Genre: Angst and Feels, Angst and Humor, Angst and Hurt/Comfort, Billy is billy-, Crack Crossover, Depressed Zim (Invader Zim), Dib will be in eventually, Fluff, Fluff and Angst, Fluff and Humor, Funny, Gen, Grim Reapers, Grim is going to adopt Zim, Grim reaper dad, Humor, I torment Zim too much, Mandy is just done with people-, Post-Traumatic Stress Disorder - PTSD, Smart Zim (Invader Zim), Zim Has Issues (Invader Zim), Zim and Billy sound the same, Zim has trauma (Invader Zim), Zim is trying to be a better person, Zim vs the tallest, the main themes of this are fluff angst and humor, there will be jokes for that-
Language: English
Status: In-Progress
Published: 2021-02-11
Updated: 2021-02-11
Packaged: 2021-03-17 21:00:28
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 1,471
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29356860
Author URL: https://archiveofourown.org/users/MopeyZim/pseuds/MopeyZim
Summary: A few years have passed after the Florpus incident that Zim had caused... the former invader decides that it isn't the best idea to stay in the place he is now. it is all just a bad memory. What does his computer suggest doing? finding a new place on Earth to live, instead of just moping around.Zim takes that advice and leaves, in the middle of the night. without letting anyone know... not even Dib...he simply wanted to start over, as a new Irken...a new PERSON..if only he knew that this new location of his would be as crazy as his former location...well, maybe "crazy" is an understatement.
Relationships: Billy & Mandy (Grim Adventures of Billy & Mandy), Billy (Billy & Mandy) & GIR (Invader Zim), Dib & Gaz (Invader Zim), Dib & Zim (Invader Zim), GIR & Zim (Invader Zim), Gaz (Invader Zim)/Mandy (Billy & Mandy), Grim & Mandy (Billy & Mandy), Grim & Zim, Grim (Billy and Mandy) & Zim (Invader Zim)
Comments: 3
Kudos: 13





	1. A new beginning

**Author's Note:**

> (Trigger warnings: mentions of torture, abuse, childhood trauma, suicidal thoughts)

It was... Quieter here.... At least during the night....

That was one of the things the tiny and scrawny little irken invader noticed about this new...habitat.... A smaller city he had come across while travelling away in his voot...

A nice, quieter, somewhat less populated city... Had become Zim's new home.

Sure, it wasn't all that different from before. It still smelled horrible and it was very loud during the daytime, but..Zim could live with it... It was better than staying...there...

Where he had pretended he was an all powerful Irken invader...

He hated living there...well, he hated living in general at this point... He had hated living there, in that place... In his former house... Ever since the Florpus incident...ever since his fight with Red and Purple...

It had been a few years since then... And all he had done was mope around the base, drowning himself in his own depression and self hatred...

It hurt to think about the past...his past.... The past in general...

He hated thinking about Spork and Miyuki...the two Tallest he had killed by mistake...

He hated to think about what hell the control brains had put him, and other defective Irkens through....

He hated thinking about how much they shocked him and tortured him for doing something wrong... For saying something wrong... For acting wrong....

For existing...

He hated to think about the times he had shared with his former friend, Purple, who had abandoned him... forgotten about him..... because he was so busy with his little boyfriend...who had treated both Purple and himself like garbage through elite years...

It was before he even became a scientist...

Tears were falling from the little Irkens face.

It hurt...it hurt to know that everything and everyone on irk focused on the fact that he was a destructive little defect....a mistake...

He wasn't even supposed to exist... That's what everyone told him....the control brains, the Taller elites... Red..

Nobody seemed to love him back on irk... Love and respect was all that he had craved from his fellow Irkens... but they all...even in the beginning... Seemed to reject him...abandon him.... Leave him for dead...

He had considered taking his life more than a few times... In his elite times....before he was a scientist...before he was in the invader academy...

The thought of ending his life came across his mind quite a bit....

He wondered what they would do if he had really killed himself then...what they would do if he killed himself on irk....

Would anyone care ...?

His mind was overflowing with thoughts.

Right now, the tiny alien was laying on the couch, safe inside of his new base, staring up at the ceiling. His little robot sidekick, Gir, was resting on the Irkens soft belly. His robotic moose, Mini-moose, a gift that had come from his once again friend 777, was fast asleep on the top of his head.

Zim would have complained if he wasn't so comfortable right now.

It was currently one in the morning.... Zim had been up pondering his thoughts almost all night. Which was not a good thing to do when he had to go to school in about five or six hours.... He wanted to sleep, but his mind was so busy.... worrying about the past...

Zim let out a small sigh as he wiped the tears falling down his cheeks with his arm, and reached into his left pocket with his free hand.

_Zim should not focus on these things right now..."_

he then pulled out a small and squeaky moose toy... One that looked old and had a missing right eye...

The one Gir had given to him after the Florpus incident... That he had before... The moose he was so desperate to get back that he ended up getting himself trapped into the house...

He gave the squeaky "stress moose" a few squeezes and yawned.

_"This is a new life....no Dib...no Tallest...no Irk....."_

He continued to squeeze the toy, until he felt satisfied...

_"They will not see you as a defective... They will see you as an odd person, since your disguise is still...poor. but they will not think of you as a defect... Nothing they would do will be nearly as bad as what the control brains and the Tallest have done..."_

Zim shivered and held the little moose close to his chest and closed his eyes, as he felt himself drifting off....

_"This Is a new life... A new start...."_

The Irken let out one more yawn before allowing himself to fall to sleep....

_"You'd better not mess it up this time"_


	2. Nothing changes

**Summary for the Chapter:**

> Grim sees that nothing has changed in the past few years

It was both annoying and intriguing how the boy could always be so excited about everything... literally... everything.

Billy was fascinated by everything. Food, clothes, bugs, dirt....you name it.

Grim would have thought that he'd have grown out if all of this as years went on.... But, nothing changed. Billy was still...Billy..

And Mandy was still as terrifying as ever... He didn't want to think of how terrifying she was at the moment.

Yes, he was still stuck with these kids... That was still the same as well

"you are going to be LATE for school if ye do not stop foolin around and start getting ready for when de BUS arrives!!!" Grim hissed at the teenager, who was jumping up and down on the couch instead of preparing himself for school.

"But, But it's Thursday! And you know what that means!!" Billy cried, jumping down from the couch onto the floor, nearly landing on his face.

"Er...do I want te know?"

"One more day until Friday!!!" Billy shouted, grinning from ear to ear.

Grim simply let out an annoyed sigh "Yes, yes....how could I not remember" he grumbled sarcastically, narrowing his eyes down at the human.

Yes... It would be Friday again... And after Friday he would be stuck with these two all weekend. It never changed. It was weekly... He slowly and painfully grew used to these two....

And... A little closer to these two...

Wait...no-

no, that wasn't possible. nope. no way

ANYWAYS....back to Grim's horrible life, yes.

As well as dealing with Billy and Mandy each weekend, he had the responsibility of keeping an eye on them whenever Billy's parents weren't home....

Well, it would be just Billy he had to watch, but Mandy was always coming over. That hadn't changed either.

He was forced to come to Mandy's place too sometimes..which was, surprisingly quieter than Billy's house.... but even so, these two took a lot of energy out of him.

One of those nights that had Grim "babysitting" was tonight...of course.

Grim glanced over at Billy, who was running around in a circle and talking about...Grim couldn't catch what exactly he was saying, he was speaking rather quickly.

Judging by the fact that he DIDN'T appear to be talking about tonight, well, not that he could hear, he assumed Billy forgot he would be watching them tonight...and he didn't feel like reminding him either. He would find out when he came home from the horrible school-

Speaking of which...

Grim heard a loud beeping noise coming from outside and hissed..

_de bus...._

"Billy! get yer a- yer little BUTT out dere! yer bus is here!" Grim snapped at the human, who was thankfully JUST done with getting ready...well, as ready as he could be. He looked like a mess, like a kid who had just come in from playing around in the dirt and/or whatever they could find.

Well, as long as he was READY....

"Huuh? oh, yeaaaah!! I'z gotta go!" Billy exclaimed happily, skipping, yes, skipping towards the door

Grim let out an annoyed groan and rushed over towards the door, quickly swinging it open. "Hurry, you little fool!" he huffed.

Billy didn't catch the hint that Grim was annoyed, he simply just hummed and walked out the door, down the sidewalk with Grim watching in the doorway.

The reaper winced as he watched Billy trip halfway to the bus. Did Billy even react? No, he just picked himself up and kept going

When he was...FINALLY on the bus, Grim sighed with relief and made his way back in the house, slamming the door behind him.

He picked up a book and sat down on the couch, shaking his head in disbelief. "These kids will be the second death of me..." he grumbled, opening his book and leaning back on the couch. While they were away, he would relax as much as he could.

Those kids were quite the handful, indeed..that was true...

Little did Grim know he would be dealing with another

**Author's Note:**

> (Alright! so, I saw that if I would keep making different works for this fanfiction that I could be spamming and taking up most of the pages on here, so I just decided to put it all into one story. I once again apoligize, I am not a very good writer but I'm gonna try. I'll try to update as much as possible if people are really into this fghdjjfh)
> 
> (Also, Zim's past and the Tallests past in this au are based off of headcanons made by my lover and I.)


End file.
